Have all the vegetables well washed and prepared as indicated in the ingredients description.
Heat the olive oil in a large saucepan over medium heat. Add the garlic and sauté for 1 minute until lightly golden. Add then the onion, the carrots and a pinch of salt and sauté for 2 more minutes until only lightly golden. Add then the diced potato and 2 tablespoons of the vegetable stock (or water if not available) and sauté for about 7 minutes. Add then the cooked beetroot dices and cover with the rest of the vegetable stock, add one teaspoon sea salt (or salt to taste), bring to a boil over medium heat and when it has reached a boil remove the saucepan from the heat.
With the help of a hand mixer (ideally a powerful one of at least 450 watt) mix it all well until perfectly combined. Serve hot, sprinkle some feta cheese and arugula and add some freshly grounded black pepper to taste.
Notes
If you use raw beetroots, to cook them steam them for about 20 minutes until you are able to pierce them easily with a fork. When peeling them, a good way to avoid the stains in your hands is to previously rub your hands with a few drops of olive oil.
Recipe by Tasty Mediterraneo at https://www.tastymediterraneo.com/beetroot-soup-with-feta-arugula/